In Jain Dharma, there is no single fixed “optimal age” for marriage prescribed for everyone.

The guiding idea is that marriage should happen after proper physical, mental, and spiritual maturity, so that both persons can follow dharma, restraint, responsibility, and mutual respect.

From a Jain point of view, the important factors are:

• Maturity of mind and character
• Ability to understand duty and responsibility
• Consent of both persons
• A life compatible with dharmic conduct

Jain teachings place more importance on right conduct, self-control, and ethics than on a particular number of years.

So, in short: the best age is when a person is truly mature and ready for a responsible, dharmic गृहस्थ जीवन (householder life).